1. Field of the Invention
The present invention relates to an image processing method, and more particularly, to a method for detecting monetary banknotes.
2. Description of the Prior Art
Automated identification and verification of known currency bills is a practical application when applied to retail and business environments. Electronic verification of known bill types helps to increase security in monetary transactions, and also prevents vendors from receiving counterfeit currencies. The currency detectors available today typically scan an image of a sample currency, from which a series of tests is performed in order to determine the validity of the sample. The tests used can include the identification of known currency sections or landmarks, holograms, reflective areas, printing patterns, and texture patterns.
However, with advancements and availability of printing technologies, the occurrence of counterfeit currency or illegally copied currency has increased. Counterfeiters nowadays have access to sophisticated equipment and methods to duplicate known currencies that are virtually indistinguishable to the human eye and to the touch.
Improvements in graphics and image duplication systems, which can include scanners, digital color copiers, and printing machinery and apparatuses, has also contributed to the increase in illegal counterfeit reproduction of various items. Counterfeiters nowadays commonly attempt to reproduce monetary banknotes such as currencies, stocks, bonds, and other valuable items for personal gain and profit. The task of distinguishing and discerning between legitimate items and copied fakes is becoming increasingly difficult as printing and reproduction improvements allow copiers to reproduce banknotes that are virtually identical to legitimate ones. Therefore, there is a need to be able to effectively and precisely discern and distinguish counterfeit monetary banknotes from authentic ones.